🆘🆘🆘 "BIG BUG" in Code PlayGround 🆘🆘🆘 or I am wrong ❓

Question

Check this short code, please
https://code.sololearn.com/cp8u053qfrKy/#py
in other 🐍IDE, 🐍 Interpreter which you are using, like Atom, vi, Visual Studio etc.
In comments give me NAME & result "True" or "False", plz. 🤔😉🙃

Answer 1

Janusz Bujak 🇵🇱 I get it... there are quite a few language design decisions in Python which I, too, struggle finding to be "acceptable." 😉

However, this particular behavior with immutable values isn't one of them.

Perhaps we're looking at this specific behavior from different perspectives. I'll list a few reasons why this treatment of Tuples makes sense to me.

Essentially, when a Tuple contains only immutable references, reusing the same Tuple makes compete sense.

It's really no different from how a string is cached and reused.

Also, this behavior isn't based in your IDE. It's based on the installed interpreter.

For more information about this behavior, take a look at this article:

https://www.journaldev.com/22925/python-id

Ultimately, I'd be more concerned about code that relies on comparing tuples in this manner, as that would reek of code smell, which is something you can control as a developer. 🤓

Answer 2

Let me think... 🤔
Yes, you are right⁉️😉

Answer 3

David Carroll
Thank you for your response & your effort. I appreciate it. You are an authority, so I'll study your comments carefully. I'm glad that I managed to trigger a discussion on the sololearn forum but wouldn't like to pass as a stubborn or boring person so I prepared a short quiz to finish the topic. It's pending now.
The question is known & the answers are:
- True ❎
- False ❎
- It depends... ✅
What is your answer?

Answer 4

Anna
Thank you for your quick answer‼️
The details of 🐍 implementation are very interesting, I read all the notes very carefully, but the problem is that the result of the program shouldn't depend on 🐍 IDE because this is not coding anymore but lottery.
I still don't know the answer to the question "x is y"⁉️
Who is right: PyCharm or PlayGround⁉️
Tell me: it's "True" or "False"⁉️

Answer 5

I'm devastated‼️🤔🤕🤢

Answer 6

Hi James,
I know all this. It's probably the result of memory optimization. It's obvious that x and y have the same value: x==y. But in my logic I can't accept that x is the same as y: x is y, despite the fact that both are immutable.
In addition, other 🐍IDE gives a different result for example PyCharm‼️

Answer 7

Hey Janusz,
It's not a bug. The output varies based on the Python implementations.
"x is y" operator is equivalent to id(x) == id(y)
You can print the ids to verify that x and y point to the same address, thus the output is True.
Try it on www.repl.it - you'll get the same result :)

Answer 8

https://stackoverflow.com/questions/49327859/why-dont-tuples-get-the-same-id-when-assigned-the-same-values

First answer, third paragraph

Answer 9

It's implementation dependent, just like many other things in other programming languages. It's up to the implementation to cache recently used objects to save a little bit of computation time compared to creating a new object. If they are cached, they'll have the same id and "x is y" will return True. If someone points out that something is "an implementation detail you can't rely on" you should probably just forget about using it because the outcome may vary.

Answer 10

One other thought to consider is we're just talking about differences in implementation details of a single nuance. If you're so "devastated" by this, you might as well learn to code in Assembly, as all interpreters and compilers deviate from different implementations, hardware, and system environments with such nuanced optimizations.

Like I said, it's just a thought to consider. 😉

Answer 11

Hmmm... 🤔 Technically, the question format calls for selecting from one of two statements.

So, using the answer options "True", "False", or "It depends..." would be ambiguous with the current wording of the question.

(a) "SOS x 3: 'Big bug' in Code Playground"

(b) "SOS x 3: or am I wrong?"

Simply answering "True" or "False" would be unclear for a question asking for (a) or (b). 😉

In the spirit of being humorous, my answer is:

x = (a) is False # True
y = (b) is True # True

print( (x) is (y) == True ) # "True" 😜

Answer 12

Nice